1. Field of the Invention
The present invention is directed toward the field of graphics, and more particularly toward generating graphics data at multiple resolutions.
2. Art Background
It is typical for graphics applications to manipulate large source images for display on a computer. For example, a source image may consist of many mega-pixels of image data. The graphics application typically operates within a broader application. For example, software, which allows a user to view and manipulate multi-level integrated circuit (“IC”) designs, utilizes a graphics application. The underlying source image for the IC design application is large, and thus the source image can't be displayed entirely on a computer display at full resolution.
In imaging applications, it is important to display images at various resolutions. For example, images are displayed at high resolutions so that image details may be visible. In addition, graphics applications require display of images at low resolutions. Since large source images can't be viewed at full resolution on a typical computer display, displaying the image at low resolutions permits viewing of large portions of the image. Typically, the IC design software permits the user, through use of a user interface, to pan large IC designs to permit viewing desired portions of the design. In addition, the IC design software permits the user to view the IC designs or portions of the IC designs at different resolutions. Accordingly, it is a desirable feature of graphics applications to provide the ability to allow a user to interact with the image data by selecting portions of the source image to view at various resolutions.
Many techniques have been developed to display data at different resolutions. Typically, data is displayed at high resolutions by scaling the image data for mapping to pixel data. Techniques have been developed to display large quantities of data at low resolutions. One technique for displaying large source images at low resolutions generates texture maps. Texture maps permit a graphics system to render low resolution images of a large source image. As disclosed herein, the techniques of the present invention permit accurate rendering of images, including low resolution images of large source images.